In busy metropolis, one of the most popular transportation tools is a taxi, which is advantageous in providing door-to-door service. To dispatch a taxi to a passenger dynamically but readily, a current practice is that a vehicle-dispatching center inquires the task-taking wishes of all the taxi drivers belonging to the same network by wireless communication when a taxi call message from a passenger is received through a phone call or online request. Then, on the basis of different coordinating conditions, one of the responsive taxis is selected to pick up the passenger. Generally, the vehicle-dispatching center gives service to different vehicle-dispatching companies. Therefore, there is a need of providing a vehicle-dispatching method and a vehicle-dispatching system for equally distributing the chances of inquiring the vehicle service task-taking wish from the vehicles of different vehicle-dispatching companies.